Process for preparing a molding comprising zinc and a titanium-containing zeolite

ABSTRACT

A process for preparing a molding comprising zinc and a titanium-containing zeolitic material having framework type MWW, comprising (i) providing a molding comprising a titanium-containing zeolitic material having framework type MWW; (ii) preparing an aqueous suspension comprising a zinc source and the molding comprising a titanium-containing zeolitic material having framework type MWW prepared in (i); (iii) heating the aqueous suspension prepared in (ii) under autogenous pressure to a temperature of the liquid phase of the aqueous suspension in the range of from 100 to 200° C., obtaining an aqueous suspension comprising a molding comprising zinc and a titanium-containing zeolitic material having framework type MWW; (iv) separating the molding comprising zinc and a titanium-containing zeolitic material having framework type MWW from the liquid phase of the suspension obtained in (iii).

This is a continuation of application Ser. No. 16/470,834, filed Jun.18, 2019, which is the National Stage of International application no.PCT/EP2018/051168, filed Jan. 18, 2018, which claims priority toEuropean patent application no. 17151943.2, filed Jan. 18, 2017, ofwhich all of the disclosures are incorporated herein by reference intheir entireties.

The present invention is directed to a process for preparing a moldingwhich comprises zinc and a titanium-containing zeolitic material whereinthe zeolitic framework structure of the zeolitic material has frameworktype MWW. Further, the present invention relates to a molding which isobtainable or obtained by said process, and further relates to the useof said molding as a catalyst.

TiMWW catalysts, for example a ZnTiMWW catalyst, i.e. catalystscomprising a titanium-containing zeolitic material having framework typeMWW which further comprises zinc, are known as excellent catalysts forthe epoxidation of propene. Such catalysts are usually prepared in asynthesis process involving a shaping stage such as an extrusion stepwhere moldings are prepared which are preferred for catalysts used inindustrial-scale processes such as the above-mentioned epoxidationprocess. Usually, the process for preparing the moldings, i.e. theshaping process, starts from a zeolitic material which comprises zinc. Aprocess for preparing such moldings is disclosed, for example, in WO2013/117536 A from which process catalysts are obtained which, withregard to a preferred use, i.e. the use as an epoxidation catalyst,exhibit most excellent characteristics. As described in WO 2013/117536A, the process is a multi-stage process wherein the shaping process isbased on a powder material of a zeolitic material which comprises zinc.Thus, the shaping process is preferably designed based on thecharacteristics of said powder material.

Thus, although the catalysts described in WO 2013/117536 A exhibitexcellent characteristics, there was a need to provide a shaping processwhich is applicable for a whole variety of titanium-containing zeoliticmaterials having framework type MWW. Further, there was a certain desireto provide a process which is even more economic than the processdescribed in WO 2013/117536 A. Surprisingly, it was found that it ispossible to incorporate zinc in the molding during the shaping step andarrive at a catalyst having the same or even improved propertiescompared with the moldings of WO 2013/117536 A when used, for example,as an epoxidation catalyst. It was further found that by doing so, itwas possible to eliminate one step of the multistage process of WO2013/117536 A thus rendering the overall process more economic which isa highly advantageous feature of a preparation process in particular ina technical field where the respectively obtained product is acommercial product used in an industrial-scale process, as it is thecase, for example, for epoxidation catalysts.

Therefore, the present invention relates to a process for preparing amolding comprising zinc and a titanium-containing zeolitic materialhaving framework type MWW, comprising

-   (i) providing a molding comprising a titanium-containing zeolitic    material having framework type MWW;-   (ii) preparing an aqueous suspension comprising a zinc source and    the molding comprising a titanium-containing zeolitic material    having framework type MWW prepared in (i);-   (iii) heating the aqueous suspension prepared in (ii) under    autogenous pressure to a temperature of the liquid phase of the    aqueous suspension in the range of from 100 to 200° C., obtaining an    aqueous suspension comprising a molding comprising zinc and a    titanium-containing zeolitic material having framework type MWW;-   (iv) separating the molding comprising zinc and a    titanium-containing zeolitic material having framework type MWW from    the liquid phase of the suspension obtained in (iii).

Step (i)

Generally, the molding provided in (i) may consist of thetitanium-containing zeolitic material having framework type MWW.Preferably, the molding comprises, in addition to thetitanium-containing zeolitic material having framework type MWW, abinder. In addition to the binder and the titanium-containing zeoliticmaterial having framework type MWW, the molding may comprise one or morefurther additional components. Preferably at least 90 weight-%, morepreferably at least 95 weight-%, more preferably at least 99 weight-%,more preferably at least 99.9 weight-% of the molding provided in (i)consist of the titanium-containing zeolitic material having frameworktype MWW and the binder. More preferably, apart from any impuritieswhich may be comprised in the binder and/or the titanium-containingzeolitic material having framework type MWW, the molding comprises nofurther component, and therefore, it is preferred that the moldingessentially consists of, more preferably consists of, the binder and thetitanium-containing zeolitic material having framework type MWW. In themolding provided in (i), the weight ratio of the titanium-containingzeolitic material having framework type MWW relative to the binder isnot subject to any specific restrictions. For example, the weight ratiomay be in the range of from 0.01:1 to 100:1 or from 0.1:1 to 10:1.Preferably, the weight ratio is in the range of from 1:1 to 9:1, morepreferably in the range of from 2:1 to 7:1, more preferably in the rangeof from 3:1 to 5:1. While the chemical nature of the binder is notsubject to any specific restrictions, it is preferred that the bindercomprises, more preferably is, a silica binder.

Therefore, it is preferred that at least 99.9 weight-% of the moldingprovided in (i) consist of the titanium-containing zeolitic materialhaving framework type MWW and a silica binder.

The geometry of the molding provided in (i) is not subject to anyspecific restrictions. Preferably, the molding provided in (i) is in theform of a tablet, a sphere, a cylinder, a star, a strand, or a trilob,wherein the molding is preferably a strand, more preferably an extrudatestrand, preferably having rectangular, triangular hexagonal, quadratic,oval, or circular cross-section. The diameter of the preferred circularcross-section is preferably in the range of from 0.2 to 5.0 mm, morepreferably in the range of from 0.5 to 3.5 mm, more preferably in therange of from 1.0 to 2.0 mm.

Preferably, the molding provided in (i) is a calcined molding, whereinthe calcination is preferably a calcination carried out in at a gasatmosphere at a temperature of the gas atmosphere preferably in therange of from 350 to 650° C., more preferably in the range of from 400to 600° C., more preferably in the range of from 450 to 550° C., whereina preferred gas atmosphere comprises air, lean air, or nitrogen such astechnical nitrogen, more preferably air.

Preferably, the molding provided in (i) exhibits one or more of thefollowing characteristics (1) to (3), preferably two or more of thefollowing characteristics (1) to (3), more preferably the followingcharacteristics (1) to (3):

-   (1) a BET specific surface area of at least 300 m²/g determined as    described in Reference Example 1 herein;-   (2) a pore volume of at least 0.9 mL/g, determined as described in    Reference Example 2 herein;-   (3) a mechanical strength in the range of from 5 to 10 N, preferably    in the range of from 6 to 9 N, determined as described in Reference    Example 3 herein.

Therefore, it is preferred that at least 99.9 weight-% of the moldingprovided in (i) consist of the titanium-containing zeolitic materialhaving framework type MWW and a silica binder, wherein the moldingexhibits the characteristics (1) to (3) described above.

There are no specific restrictions how the molding provided in (i) isprepared. A preferred process for the preparation of the moldingcomprises

-   (i.1) preparing a mixture comprising the titanium-containing    zeolitic material having framework type MWW, a binder or a source of    a binder, a pasting agent and optionally a pore-forming agent;-   (i.2) shaping the mixture prepared in (i.1), obtaining a molding    comprising the titanium-containing zeolitic material having    framework type MWW and a binder or a source of a binder:-   (i.3) drying the molding obtained in (i.2);-   (i.4) calcining the dried molding obtained in (i.3), obtaining the    molding comprising the titanium-containing zeolitic material having    framework type MWW and a binder.

Preferably, the pasting agent according to (i) comprises one or more ofwater and a hydrophilic polymer, more preferably one or more of waterand a carbohydrate, more preferably water and a carbohydrate. Thecarbohydrate preferably comprises, more preferably is, one or more of acellulose and a cellulose derivative, more preferably comprises, morepreferably is, one or more of a cellulose, a cellulose ether and acellulose ester, more preferably comprises, more preferably is, acellulose ether, more preferably a cellulose alkyl ether, morepreferably a methyl cellulose. Therefore, it is preferred that thepasting agent according to (i.1) comprises, more preferably is, waterand a methyl cellulose.

If the mixture prepared in (i.1) comprises a pore-forming agent, it ispreferred that the pore-forming agent comprises, preferably is, amesopore-forming agent, which is preferably one or more a polyalkyleneoxide such as polyethylene oxide, a polystyrene, a poly-acrylate, apolymethacrylate, a polyolefin, a polyamide, and a polyester.Polyethylene oxide may be preferred, wherein the may have a meanmolecular weight MW (g/mol) in the range of from 100,000 to 6,000,000,such as of about 4,000,000.

Preferably, the binder or precursor of a binder of the mixture providedin (i.1) comprises, more preferably is, a silica binder or a precursorof a silica binder. Regarding the precursor of the silica binder, it isgenerally possible to use both colloidal silica and so-called “wetprocess” silica and so-called “dry process” silica. Particularlypreferably this silica is amorphous silica, the size of the silicaparticles being, for example, in the range of from 1 to 100 nm and thesurface area of the silica particles being in the range of from 50 to500 m²/g. Colloidal silica, preferably as an alkaline and/or ammoniacalsolution, more preferably as an ammoniacal solution, is commerciallyavailable, inter alia, for example as Ludox®, Syton®, Nalco® orSnowtex®. “Wet process” silica is commercially available, inter alia,for example as HiSil®, Ultrasil®, Vulcasil®, Santocel®,Valron-Estersil®, Tokusil® or Nipsil®. “Dry process” silica iscommercially available, inter alia, for example as Aerosil®, Reolosil®,Cab-O-Sil®, Fransil® or ArcSilica®. Inter alia, an ammoniacal solutionof colloidal silica is preferred in the present invention. Preferablyaccording to the present invention, the precursor of the silica bindercomprised in the mixture according to (i.1) comprises, more preferablyis, one or more of a silica gel, a precipitated silica, a fumed silica,and a colloidal silica. More preferably, the precursor of the silicabinder comprised in the mixture according to (i.1) comprises, preferablyis, a colloidal silica. More preferably, the precursor of the silicabinder comprised in the mixture according to (i.1) consists of acolloidal silica, wherein more preferably, the silica binder or theprecursor comprises, preferably is, a colloidal silica.

Preferably, in the mixture prepared in (i.1), the weight ratio of thetitanium-containing zeolitic material having framework type MWW relativeto the silica comprised in the binder or the precursor of the binder isin the range of from 1:1 to 9:1, more preferably in the range of from2:1 to 7:1, more preferably in the range of from 3:1 to 5:1.

Preferably, the mixture prepared in (i.1) does not comprise zinc,neither in the binder nor in the titanium-containing zeolitic materialhaving framework type MWW nor in any other components of the mixture.The term “does not contain zinc” does not exclude a minimum amount ofzinc which may be present in the mixture due to impurities in one ormore components of the mixture which cannot be avoided.

Preferably at least 99 weight-%, preferably at least 99.5 weight-%, morepreferably at least 99.9 weight-% of the mixture prepared in (i.1)consist of the titanium-containing zeolitic material having frameworktype MWW, the binder or the precursor of the binder, and the pastingagent.

Preferably, preparing the mixture according to (i.1) comprisesmechanically agitating, more preferably kneading the mixture, whereinthe kneading is preferably carried out until the individual componentsof the mixture which were added in a suitable sequence together form ahomogenous mass.

Preferably, shaping according to (i.2) comprises extruding the mixtureprepared in (i.1). Regarding the extruding according to (i.2), nospecific restrictions exist. Generally, every method of extruding themixture obtained from (i.1) can be employed. The term “extrusion” asused herein relates to a method from which moldings having anessentially fixed cross-sectional profile are obtained wherein thecomposition obtained from (iv) is suitably pushed through a suitable diewhich exhibits the desired cross-section. The molding which is obtainedfrom the extruder used can be cut downstream of the respectively useddie, for example using a suitable air stream and/or a mechanical cuttingdevice such as a suitable wire. If it is not necessary to obtainmoldings having essentially identical length, it is also possible thatthe molding obtained from the extruder is not cut but breaks under itsown weight downstream of the die leading to moldings having differentlengths. The cross-section of the molding can be, for example,circle-shaped, oval, star-shaped, and the like. Preferably, according tothe present invention, the molding has a circle-shaped cross-sectionwherein the diameter is preferably in the range of from 0.2 to 5.0 mm,more preferably in the range of from 0.5 to 3.5 mm, more preferably inthe range of from 1.0 to 2.0 mm.

Preferably, according to (i.3), the molding is dried. The drying ispreferably carried out in a gas atmosphere at a temperature of the gasatmosphere preferably in the range of from 80 to 200° C., morepreferably in the range of from 90 to 175° C., more preferably in therange of from 100 to 150° C. Every suitable gas atmosphere can be usedwherein a preferred gas atmosphere comprises air, lean air, or nitrogensuch as technical nitrogen.

Preferably, according to (i.4), the dried molding obtained from (i.3) iscalcined. The calcination is preferably carried out in at a gasatmosphere at a temperature of the gas atmosphere preferably in therange of from 350 to 650° C., more preferably in the range of from 400to 600° C., more preferably in the range of from 450 to 550° C. Everysuitable gas atmosphere can be used wherein a preferred gas atmospherecomprises air, lean air, or nitrogen such as technical nitrogen.

Regarding the titanium-containing zeolitic material having frameworktype MWW comprised in the molding provided in (i), no specificrestrictions exist with regard to is chemical composition. Therefore, itmay be possible that in addition to Ti, Si, O and H, the zeoliticmaterial contains further framework and/or extra-framework elements forexample one or more three-valent, one or more tetra-valent, and/or oneor more penta-valent framework elements such as Al, In, Ga, B, Ge, Sn,and the like. Preferably, at least 95 weight-%, more preferably at least98 weight-%, more preferably at least 99 weight-% of thetitanium-containing zeolitic material having framework type MWWcomprised in the molding provided in (i) consist of Ti, Si, O, and Hwherein the framework of the zeolitic material preferably essentiallyconsists of Ti, Si and O. The titanium content of thetitanium-containing zeolitic material having framework type MWWcomprised in the molding provided in (i) is not subject to any specificrestrictions. Preferably, the titanium-containing zeolitic materialhaving framework type MWW comprised in the molding provided in (i) has atitanium content, calculated as elemental titanium, in the range of from0.1 to 5 weight-%, more preferably in the range of from 0.5 to 3weight-%, more preferably in the range of from 1 to 3 weight-%, based onthe total weight of the titanium-containing zeolitic material havingframework type MWW. A preferred range may be of from 1.5 to 2 weight-%.Preferably, the titanium-containing zeolitic material having frameworktype MWW comprised in the molding provided in (i) has a silicon content,calculated as elemental silicon, in the range of from 30 to 60 weight-%,preferably in the range of from 35 to 55 weight-%, more preferably inthe range of from 40 to 50 weight-%, more preferably in the range offrom 1 to 3 weight-%, based on the total weight of thetitanium-containing zeolitic material having framework type MWW. Apreferred range may be of from 44 to 48 weight-%. Therefore, it ispreferred that the titanium-containing zeolitic material havingframework type MWW comprised in the molding provided in (i) has atitanium content in the range of from 1 to 3 weight-% and a siliconcontent in the range of from 40 to 50 weight-%, wherein it may bepreferred that it has a titanium content in the range of from 1.5 to 2weight-% and a silicon content in the range of from 44 to 48 weight-%.

Preferably, the titanium-containing zeolitic material having frameworktype MWW comprised in the molding provided in (i) has a total organiccarbon content of at most 0.1 weight-%, based on the total weight of thetitanium-containing zeolitic material having framework type MWW.Preferably, the titanium-containing zeolitic material having frameworktype MWW comprised in the molding provided in (i) has a boron content,calculate as elemental boron, of at most 0.1 weight-% or at most 0.5weight-%, more preferably of at most 0.5 weight %, based on the totalweight of the titanium-containing zeolitic material having frameworktype MWW. Preferably, the titanium-containing zeolitic material havingframework type MWW comprised in the molding provided in (i) has a BETspecific surface area of at least 400 m²/g, preferably in the range offrom 400 to 600 m²/g, more preferably in the range of from 450 to 550m²/g, wherein the BET specific surface area is determined as describedin Reference Example 1 herein. Preferably, the titanium-containingzeolitic material having framework type MWW comprised in the moldingprovided in (i) has a crystallinity of at least 70%, preferably in therange of from 70 to 90%, more preferably in the range of from 70 to 80%,wherein the crystallinity is determined as described in ReferenceExample 4 herein. Preferably, the titanium-containing zeolitic materialhaving framework type MWW comprised in the molding provided in (i) is inthe form of a powder having a particle size distribution characterizedby a Dv10 value in the range of from 1 to 10 micrometer, preferably inthe range of from 1.5 to 10 micrometer, more preferably in the range offrom 2 to 6 micrometer, a Dv50 value in the range of from 5 to 50micrometer, preferably in the range of from 7 to 50 micrometer, morepreferably in the range of from 8 to 30 micrometer, and a Dv90 value inthe range of from 12 to 200 micrometer, preferably in the range of from12 to 90 micrometer, more preferably in the range of from 13 to 70micrometer, wherein the particle size distribution is determined asdescribed in Reference Example 5 herein. The titanium-containingzeolitic material having framework type MWW comprised in the moldingprovided in (i) may be a spray powder, i.e. a powder obtained from aspray-drying process, or may be powder which is obtained from otherprocesses which may result in a powder having the above-mentionedpreferred particle size distribution, such as flash drying or may bemicrowave drying.

According to preferred embodiments of the present invention, thetitanium-containing zeolitic material having framework type MWWcomprised in molding prepared in (i), for example comprised in themixture prepared in (i.1), is obtainable or obtained by a processcomprising

-   (a) preparing a boron-containing zeolitic material having framework    type MWW, wherein at least 99 weight-% of the zeolitic framework    consist of B, Si, O and H;-   (b) deboronating the boron-containing zeolitic material having    framework type MWW prepared in (a), obtaining a deboronated zeolitic    material having framework type MWW, wherein at least 99 weight-% of    the zeolitic framework of the deboronated zeolitic material consist    of B, Si, O and H, and wherein the zeolitic framework of the    deboronated zeolitic material has empty framework sites;-   (c) incorporating titanium into the deboronated zeolitic material    obtained from (b), comprising preparing an aqueous synthesis mixture    containing the deboronated zeolitic material obtained from (b), a    titanium source, and an MWW template compound; and hydrothermally    synthesizing a titanium-containing zeolitic material having    framework type MWW from the aqueous synthesis mixture prepared in    (c), obtaining a mother liquor comprising a titanium-containing    zeolitic material having framework type MWW;-   (d) separating the titanium-containing zeolitic material having    framework type MWW synthesized in (c) from the mother liquor;-   (e) treating the separated titanium-containing zeolitic material    having framework type MWW obtained from (d) with an aqueous solution    having a pH of at most 5;-   (f) separating the titanium-containing zeolitic material having    framework type MWW obtained from (e) from the aqueous solution,    optionally followed by washing the separated the titanium-containing    zeolitic material having framework type MWW;-   (g) preparing a suspension, preferably an aqueous suspension,    containing the titanium-containing zeolitic material having    framework type MWW obtained from (f), and subjecting the suspension    to spray-drying;-   (h) calcining the titanium-containing zeolitic material having    framework type MWW obtained from (g).

According to a preferred embodiment of the present invention, providingthe titanium-containing zeolitic material having framework type MWWcomprised in molding prepared in (i) comprises

-   (a) preparing a boron-containing zeolitic material having framework    type MWW, wherein at least 99 weight-% of the zeolitic framework    consist of B, Si, O and H;-   (b) deboronating the boron-containing zeolitic material having    framework type MWW prepared in (a), obtaining a deboronated zeolitic    material having framework type MWW, wherein at least 99 weight-% of    the zeolitic framework of the deboronated zeolitic material consist    of B, Si, O and H, and wherein the zeolitic framework of the    deboronated zeolitic material has empty framework sites;-   (c) incorporating titanium into the deboronated zeolitic material    obtained from (b), comprising preparing an aqueous synthesis mixture    containing the deboronated zeolitic material obtained from (b), a    titanium source, and an MWW template compound; and hydrothermally    synthesizing a titanium-containing zeolitic material having    framework type MWW from the aqueous synthesis mixture prepared in    (c), obtaining a mother liquor comprising a titanium-containing    zeolitic material having framework type MWW;-   (d) separating the titanium-containing zeolitic material having    framework type MWW synthesized in (c) from the mother liquor;-   (e) treating the separated titanium-containing zeolitic material    having framework type MWW obtained from (d) with an aqueous solution    having a pH of at most 5;-   (f) separating the titanium-containing zeolitic material having    framework type MWW obtained from (e) from the aqueous solution,    optionally followed by washing the separated the titanium-containing    zeolitic material having framework type MWW;-   (g) preparing a suspension, preferably an aqueous suspension,    containing the titanium-containing zeolitic material having    framework type MWW obtained from (f), and subjecting the suspension    to spray-drying;-   (h) calcining the titanium-containing zeolitic material having    framework type MWW obtained from (g).

According to a preferred embodiment of the present invention, preparingthe boron-containing zeolitic material having framework type MWW in (a)comprises

-   (a.1) preparing an aqueous synthesis mixture comprising a silicon    source, a boron source, and an MWW template compound;-   (a.2) hydrothermally synthesizing a precursor of the    boron-containing zeolitic material having framework type MWW from    the aqueous synthesis mixture prepared in (a.1), obtaining a mother    liquor comprising the precursor of the boron-containing zeolitic    material having framework type MWW;-   (a.3) separating the precursor of the boron-containing zeolitic    material having framework type MWW from the mother liquor, obtaining    the separated precursor of the boron-containing zeolitic material    having framework type MWW;-   (a.4) calcining the separated precursor of the boron-containing    zeolitic material having framework type MWW, obtaining the    boron-containing zeolitic material having framework type MWW.

In the aqueous synthesis mixture prepared in (a.1), the molar ratio ofthe MWW template compound relative to Si, calculated as elementalsilicon and comprised in the silicon source, is preferably at least0.4.1, more preferably in the range of from 0.4:1 to 2.0:1, morepreferably in the range of from 0.6:1 to 1.9:1, more preferably in therange of from 0.9:1 to 1.4:1. In the aqueous synthesis mixture preparedin (a.1), the molar ratio of water relative to the silicon source,calculated as elemental silicon, is preferably in the range of from 1:1to 30:1, more preferably in the range of from 3:1 to 25:1, morepreferably in the range of from 6:1 to 20:1. In the aqueous synthesismixture prepared in (a.1), the molar ratio of the boron source,calculated as elemental boron, relative to the silicon source,calculated as elemental silicon, is preferably in the range of from0.4:1 to 2.0:1, more preferably in the range of from 0.6:1 to 1.9:1,more preferably in the range of from 0.9:1 to 1.4:1. In (a.1), the boronsource is preferably one or more of boric acid, a borate, and boronoxide, more preferably boric acid. In (a.1), the silicon source ispreferably one or more of fumed silica and colloidal silica, morepreferably colloidal silica, more preferably ammonia-stabilizedcolloidal silica. In (a.1), the MWW template compound is preferably oneor more of piperidine, hexamethylene imine,N,N,N,N′,N′,N′-hexamethyl-1,5-pentanediammonium ion,1,4-bis(N-methylpyrrolidini-um)butane, octyltrimethylammonium hydroxide,heptyltrimethylammonium hydroxide, and hexyltrimethylammonium hydroxide,more preferably piperidine. Preferably at least 99 weight-%, morepreferably at least 99.5 weight-%, more preferably at least 99.9weight-% of the aqueous synthesis mixture prepared in (a.1) consist ofwater, the boron source, the silicon source, and the MWW templatecompound.

In (a.2), the hydrothermally synthesizing is carried out at atemperature of the aqueous synthesis mixture preferably in the range offrom 160 to less than 180° C., more preferably in the range of from 170to 177° C. In (a.2), the hydrothermally synthesizing is carried out fora period of time preferably in the range of from 1 to 72 h, morepreferably in the range of from 6 to 60 h, more preferably in the rangeof from 12 to 50 h. In (a.2), the hydrothermally synthesizing ispreferably carried out in a closed system under autogenous pressure. ThepH of the mother liquor obtained in (a.2) is preferably greater than 10,more preferably at least 10.5, more preferably at least 11, and after(a.2) and before (a.3), the pH of the mother liquor is preferablyadjusted to a value of at most 10, more preferably at most 9, morepreferably at most 8, more preferably in the range of from 7 to 8.Preferably, the pH of the liquid phase of the mother liquor is adjustedby subjecting the liquid phase of the mother liquor to an acidtreatment, wherein the acid is preferably an inorganic acid, morepreferably one or more of phosphoric acid, sulphuric acid, hydrochloricacid, and nitric acid, the acid more preferably being nitric acid.

The separating according to (a.3) preferably comprises subjecting themother liquor obtained in (a.2) to filtration. The separating accordingto (a.3) preferably comprises drying, preferably spray-drying.

In (a.4), the separated precursor of the boron-containing zeoliticmaterial having framework type MWW is calcined at a temperaturepreferably in the range of from 400 to 800° C., more preferably from 600to 700° C.

In (b), the boron-containing zeolitic material having framework type MWWprepared in (a) is preferably deboronated by treating theboron-containing zeolitic material having framework type MWW with aliquid solvent system, obtaining the deboronated zeolitic materialhaving framework type MWW, wherein preferably at least 99 weight-% ofthe zeolitic framework of the deboronated zeolitic material consist ofB, Si, O and H and wherein the zeolitic framework of the deboronatedzeolitic material preferably has empty framework sites. Preferably, thedeboronated zeolitic material having framework type MWW obtained from(b) has a molar ratio of boron, calculated as B₂O₃, relative to silicon,calculated as SiO₂, of at most 0.02:1, more preferably at most 0.01:1,more preferably in the range of from 0.001:1 to 0.01:1, more preferablyin the range of from 0.001:1 to 0.003:1, wherein preferably at least99.5 weight-%, more preferably least 99.9 weight-% of the deboronatedzeolitic material having framework type MWW consist of B, Si, O and H.In (b), the liquid solvent system is preferably one or more of water,methanol, ethanol, propanol, ethane-1,2-diol, propane-1,2-diol,propane-1,3-diol, and propane-1,2,3-triol, wherein preferably, theliquid solvent system does not contain an inorganic acid and an organicacid. Prior to (b), the weight ratio of the liquid solvent systemrelative to the zeolitic material having framework type MWW ispreferably in the range of from 5:1 to 40:1, more preferably in therange of from 7.5:1 to 30:1, more preferably in the range of from 10:1to 20:1. In (b), the treating with the liquid solvent system ispreferably carried out at a temperature of the liquid solvent system inthe range of from 50 to 125° C., more preferably in the range of from 90to 115° C., more preferably in the range of from 95 to 105° C. In (b),the treating with the liquid solvent system is preferably carried outfor a period in the range of from 6 to 20 h, more preferably in therange of from 7 to 17 h, more preferably in the range of from 8 to 12 h.In (b), the treating with the liquid solvent system is preferablycarried out in an open system under reflux or in a closed system withoutreflux. Preferably, (b) comprises drying, more preferably spray-dryingthe deboronated zeolitic material having framework type MWW. Preferably,the deboronated zeolitic material having framework type MWW obtainedfrom (b) is not subjected to calcination prior to (c).

In (c), the MWW template compound is preferably one or more ofpiperidine, hexamethylene imine,N,N,N,N′,N′,N′-hexamethyl-1,5-pentanediammonium ion,1,4-bis(N-methylpyrrolidinium)butane, octyltrimethylammonium hydroxide,heptyltrimethylammonium hydroxide, and hexyltrimethylammonium hydroxide,more preferably piperidine. In (c), the titanium source is preferablyone ore more of tetra-n-butyl orthotitanate, tetraiso-propylorthotitanate, tetraethyl orthotitanate, titanium dioxide, titaniumtetrachloride, and titanium tert-butoxide, the titanium sourcepreferably being tetra-n-butyl orthotitanate. In the aqueous synthesismixture in (c), the molar ratio of Ti, calculated as TiO₂ and comprisedin the titanium source, relative to Si, calculated as SiO₂ and comprisedin the deboronated zeolitic material having framework type MWW, ispreferably in the range of from 0.005:1 to 0.1:1, more preferably therange of from 0.01:1 to 0.08:1, more preferably the range of from 0.02:1to 0.06:1, the molar ratio of H₂O relative to Si, calculated as SiO₂ andcomprised in the deboronated zeolitic material having framework typeMWW, is preferably in the range of from 8:1 to 20:1, more preferably therange of from 10:1 to 18:1, more preferably the range of from 12:1 to16:1, and the molar ratio of the MWW template compound relative to Si,calculated as SiO₂ and comprised in deboronated zeolitic material havingframework type MWW, is preferably in the range of from 0.5:1 to 1.7:1,more preferably the range of from 0.8:1 to 1.5:1, more preferably therange of from 1.0:1 to 1.3:1. In (c), the hydrothermal synthesizing ispreferably carried out at a temperature in the range of from 80 to 250°C., more preferably the range of from 120 to 200° C., more preferablythe range of from 160 to 180° C., preferably in a closed system underautogenous pressure. Preferably, neither during (c), nor after (c) andbefore (d), the titanium-containing zeolitic material having frameworktype MWW is separated from its mother liquor.

Preferably, the mother liquor subjected to (d) comprising thetitanium-containing zeolitic material having framework type MWW has asolids content, optionally after concentration or dilution, in the rangeof from 5 to 25 weight-%, more preferably in the range of from 10 to 20weight-%, based on the total weight of the mother liquor comprising thetitanium-containing zeolitic material having framework type MWW.Preferably, the separating according to (d) comprises spray-drying,wherein during spray-drying in (d), the drying gas inlet temperature ispreferably in the range of from 200 to 700° C., preferably in the rangeof from 200 to 350° C., and the drying gas outlet temperature ispreferably in the range of from 70 to 190° C.

In (e), the weight ratio of the aqueous solution relative to thetitanium-containing zeolitic material having framework type MWW ispreferably in the range of from 10:1 to 30:1, more preferably in therange of from 15:1 to 25:1, more preferably in the range of from 18:1 to22:1, and the aqueous solution preferably comprises an inorganic acid,more preferably one or more of phosphoric acid, sulphuric acid,hydrochloric acid, and nitric acid, more preferably nitric acid.Preferably, after (d) and before (e), the separated thetitanium-containing zeolitic material having framework type MWW obtainedfrom (d) is not subjected to calcination. In (e), the aqueous solutionpreferably has a pH in the range of from 0 to 5, more preferably in therange of from 0 to 3, more preferably in the range of from 0 to 2. In(e), the titanium-containing zeolitic material having framework type MWWis preferably treated with the aqueous solution at a temperature of theaqueous solution in the range of from 50 to 175° C., more preferably inthe range of from 70 to 125° C., more preferably in the range of from 95to 105° C., preferably in a closed system under autogenous pressure.

The separating of the titanium-containing zeolitic material havingframework type MWW according to (f) preferably comprises washing thetitanium-containing zeolitic material having framework type MWW. Theseparating of the titanium-containing zeolitic material having frameworktype MWW according to (f) preferably comprises drying thetitanium-containing zeolitic material having framework type MWW. Theseparating of the titanium-containing zeolitic material having frameworktype MWW according to (f) preferably comprises preparing a suspension,preferably an aqueous suspension containing the titanium-containingzeolitic material having framework type MWW obtained from (e), saidsuspension having a solids content preferably in the range of from 5 to25 weight-%, more preferably in the range of from 10 to 20 weight-%,based on the total weight of the suspension, and subjecting thesuspension to spray-drying. During spray-drying, the drying gas inlettemperature is preferably in the range of 200 to 700° C., morepreferably in the range of from 200 to 330° C., and the drying gasoutlet temperature is preferably in the range of from 100 to 180° C.,more preferably in the range of from 120 to 180° C.

The calcining in (h) is preferably carried out at a temperature in therange of from 400 to 800° C., more preferably in the range of from 600to 700° C.

Step (ii)

Generally, there are no specific restrictions regarding the chemicalnature of the zinc source used according to (ii). Preferably, the zincsource comprises, more preferably consists of, a zinc compound which issoluble in water, preferably at the temperature and pressure of theliquid aqueous phase according to (iii). More preferably, the zincsource comprises one or more of a zinc salt of an organic or inorganicacid, preferably comprises one or more of zinc acetate, zinc benzoate,zinc borate, zinc bromide, zinc chloride, zinc formate, zinc gluconate,zinc lactate, zinc laurate, zinc malate, zinc nitrate, zinc perborate,zinc sulfate, zinc sulfamate, zinc tartrate, more preferably compriseszinc acetate, more preferably comprises zinc acetate dihydrate. Morepreferably, the zinc source consists of one or more of a zinc salt of anorganic or inorganic acid, preferably consists of one or more of zincacetate, zinc benzoate, zinc borate, zinc bromide, zinc chloride, zincformate, zinc gluconate, zinc lactate, zinc laurate, zinc malate, zincnitrate, zinc perborate, zinc sulfate, zinc sulfamate, zinc tartrate,more preferably consists of zinc acetate, more preferably consists ofzinc acetate dihydrate.

In the aqueous suspension prepared in (ii), the weight ratio of zinc,calculated as elemental zinc and comprised in the zinc source relativeto the titanium-containing zeolitic material having framework type MWWcomprised in the molding is preferably in the range of from 0.005:1 to0.1:1, more preferably in the range of from 0.01:1 to 0.075:1, morepreferably in the range of from 0.02:1 to 0.05:1, more preferably in therange of from 0.03:1 to 0.04:1. Further in the aqueous suspensionprepared in (ii), the weight ratio of the titanium-containing zeoliticmaterial having framework type MWW comprised in the molding relative towater is preferably in the range of from 0.01:1 to 0.1:1, morepreferably in the range of from 0.02:1 to 0.075:1, more preferably inthe range of from 0.03:1 to 0.05:1.

Generally, it is conceivable that in addition to the water, the zincsource and the titanium-containing zeolitic material having frameworktype MWW, the aqueous suspension comprises one or more further suitablecomponents. Preferably at least 99 weight-%, more preferably at least99.5 weight-%, more preferably at least 99.9 weight-% of the aqueoussuspension prepared in (ii) consist of water, the zinc source and themolding comprising the titanium-containing zeolitic material havingframework type MWW.

It is conceivable that at least a portion of the water comprised in theaqueous suspension is ammonia-stabilized water.

Step (iii)

According to (iii), it is preferred that the aqueous suspension preparedin (ii) is heated to and kept at a temperature of the liquid phase ofthe aqueous suspension in the range of from 100 to 190° C., morepreferably in the range of from 110 to 175° C., more preferably in therange of from 115 to 160° C., more preferably in the range of from 120to 150° C. Preferred ranges are, for example, of from 120 to 130° C. orfrom 125 to 135° C. or from 130 to 140° C. or from 135 to 145° C. orfrom 140 to 150° C. Preferably, in (iii), the suspension prepared in(ii) is kept at this temperature for a period of time in the range offrom 1 to 24 hours, more preferably in the range of from 2 to 17 hours,more preferably in the range of from 3 to 10 hours.

Preferably, during heating or during keeping or during heating andkeeping in (iii), the suspension prepared in (ii) is not stirred.

Step (iv)

Generally, there are no specific restrictions how the separating in (iv)is carried out. Preferably, the separating in (iv) comprises subjectingthe aqueous suspension obtained from (iii) to filtration orcentrifugation, optionally followed by washing, obtaining the separatedmolding comprising zinc and a titanium-containing zeolitic materialhaving framework type MWW. All types of filters are conceivable whichpreferably exhibit, during filtration, a loss of at most 10 weight-% insolid material. Conceivable filters include, for example, decantors,slot sieves, nutsch-type filters, and the like.

Step (v)

Preferably, the molding separated according to (iv) is subjected todrying according to (v). Prior to drying, it is conceivable to subjectthe molding separated according to (iv) to pre-drying in a suitable gasatmosphere such as nitrogen, air or lean air at a temperature of the gasatmosphere preferably of at most 50° C., more preferably of at most 40°C., more preferably of at most ° C., more preferably in the range offrom 10 to 30° C., more preferably in the range of from 20 to 30° C.

Preferably, the separated molding comprising zinc and atitanium-containing zeolitic material having framework type MWW obtainedfrom (iv) is dried at a temperature in the range of from 80 to 200° C.,more preferably in the range of from 90 to 175° C., more preferably inthe range of from 100 to 150° C. Preferably, in (v), the molding isdried at this temperature for a period of time in the range of from 0.5to 12 hours, more preferably in the range of from 1 to 8 hours, morepreferably in the range of from 2 to 6 hours. Preferably, the separatedmolding comprising zinc and a titanium-containing zeolitic materialhaving framework type MWW is dried in a gas atmosphere comprisingoxygen, preferably air or lean air, more preferably air, wherein thedrying temperature mentioned above is the temperature of the gasatmosphere used for drying.

Step (vi)

Preferably, the molding separated according to (iv) or the moldingobtained from drying according to (v), preferably the molding obtainedfrom drying according to (v), is subjected to calcining according to(vi).

Preferably, the preferably dried molding comprising zinc and atitanium-containing zeolitic material having framework type MWW iscalcined at a temperature in the range of from 300 to 600° C.,preferably in the range of from 350 to 550° C., more preferably in therange of from 400 to 500° C. If calcination is carried out in a batchprocess, it may be preferred to carry out the calcining for a period oftime in the range of from 0.1 to 6 hours, more preferably in the rangeof from 0.2 to 4 hours, more preferably in the range of from 0.5 to 3hours. The calcining can also be carried out in a continuous processusing, for example, a rotary furnace, a band calciner, or the like.Preferably, the preferably dried molding comprising zinc and atitanium-containing zeolitic material having framework type MWW iscalcined in a gas atmosphere comprising oxygen, preferably air or leanair, more preferably air, wherein the calcining temperature mentionedabove is the temperature of the gas atmosphere used for calcining.

According to the present invention, it is preferred that during theentire process, the molding is not subjected to water-steaming, morepreferably not subjected to steaming.

Molding and Use Thereof

Further, the present invention relates to a molding comprising zinc anda titanium-containing zeolitic material having framework type MWW,obtainable or obtained by a process as described hereinabove, preferablyaccording to a process as described hereinabove comprising dryingaccording to (v), more preferably according to process comprisingcalcining according to (vi), more preferably comprising drying accordingto (v) and calcining according to (vi).

Further, the present invention relates to a molding comprising zinc anda titanium-containing zeolitic material having framework type MWW,wherein in the molding, the weight ratio of zinc relative to thetitanium-containing zeolitic material having framework type MWW is inthe range of from 0.005:1 to 0.1:1, preferably in the range of from0.01:1 to 0.075:1, more preferably in the range of from 0.02:1 to0.05:1, more preferably in the range of from 0.03:1 to 0.04:1.

Preferably, at least 99 weight-%, more preferably at least 99.5 weight-%of the molding consist of zinc, Ti, Si, O, and H. Preferably, themolding essentially consists of zinc, Ti, Si, O, and H. The term“essentially consists of” as used in this context of the presentinvention relates to a molding which, apart from any impurities whichcannot be avoided in a given process for the preparation of the molding,the molding consists of zinc, Ti, Si, O, and H.

Preferably, the molding has a BET specific surface are of at least 200to m²/g, more preferably of at least 225 m²/g, more preferably of atleast 250 m²/g, wherein the BET specific surface area is determined asdescribed in Reference Example 1 herein.

Preferably, the molding has a crystallinity of at least 50%, preferablyin the range of from 50 to 90%, wherein the crystallinity is determinedas described in Reference Example 4 herein.

Preferably, the molding has a porosity of at least 0.9 mL/g, determinedas described in Reference Example 2 herein.

Preferably, the molding has a mechanical strength in the range of from 9to 23 N, preferably in the range of from 11 to 18 N, more preferably inthe range of from 15 to 18 N, determined as described in ReferenceExample 3 herein.

Preferably, the molding exhibits a water adsorption capacity in therange of from 5 to 14 weight-%, preferably in the range of from 6 to 13weight-%, more preferably in the range of from 8 to 12 weight-%,determined as described in Reference Example 7 herein.

Preferably, the molding exhibits a PO test parameter of at least 8%,preferably of at least 9%, determined as described in Reference Example6 herein.

The molding of the present invention can be used for any conceivablepurpose, including, but not limited to, an absorbent, an adsorbent, amolecular sieve, a catalyst, a catalyst carrier or an intermediate forpreparing one or more thereof. Preferably, the molding is used as acatalyst, more preferably as a catalyst for converting a hydrocarbon,more preferably for oxidizing a hydrocarbon, more preferably forepoxidizing a hydrocarbon having at least one carbon-carbon double bond,more preferably for epoxidizing an alkene. Preferred alkenes include,bur are not limited to, ethene, propene, 1-butene, 2-butene, 1-penteneand 2-pentene. Propene is more preferred. Therefore, the presentinvention preferably relates to the use of the molding as a catalyst forepoxidizing propene. Preferably, the alkene, more preferably thepropene, is epoxidized in the presence of a solvent, wherein the solventpreferably comprising a nitrile, more preferably comprises acetonitrile.More preferably, the solvent is acetonitrile, optionally in combinationwith water. Epoxidizing can be carried out using any conceivableepoxidation agent including the preferred hydrogen peroxide which can beused as such or can be formed in situ in the respective epoxidationreaction.

Further, the present invention relates to a method for catalyticallyconverting a hydrocarbon, preferably for catalytically oxidizing ahydrocarbon, more preferably for catalytically epoxidizing a hydrocarbonhaving at least one carbon-carbon double bond, more preferably forcatalytically epoxidizing an alkene, wherein the hydrocarbon, preferablythe hydrocarbon having at least one carbon-carbon double bond, morepreferably the alkene is brought into contact with the molding accordingto the present invention. Preferred alkenes include, bur are not limitedto, ethene, propene, 1-butene, 2-butene, 1-pentene and 2-pentene.Propene is more preferred. Preferably, the alkene, more preferably thepropene, is epoxidized in the presence of a solvent, wherein the solventpreferably comprising a nitrile, more preferably comprises acetonitrile.More preferably, the solvent is acetonitrile, optionally in combinationwith water. Epoxidizing can be carried out using any conceivableepoxidation agent including the preferred hydrogen peroxide which can beused as such or can be formed in situ in the respective epoxidationreaction.

Yet further, the present invention relates to a catalytic systemcomprising a catalyst comprising a molding according to any one ofembodiments 52 to 60, and at least one potassium salt, wherein the atleast one potassium salt is selected from the group consisting of atleast one inorganic potassium salt, at least one organic potassium salt,and combinations of at least one inorganic potassium salt and at leastone organic potassium salt. The at least one potassium salt ispreferably selected from the group consisting of at least one inorganicpotassium salt selected from the group consisting of potassiumhydroxide, potassium chloride, potassium nitrate, at least one organicpotassium salt selected from the group consisting of potassium formate,potassium acetate, potassium carbonate, and potassium hydrogencarbonate, and a combination of at least one of the at least oneinorganic potassium salts and at least one of the at least one organicpotassium salts. Preferably, said catalytic system is a catalytic systemfor the epoxidation of an alkene, preferably propene. Preferably, saidcatalytic system is obtainable or obtained by a preferably continuousprocess comprising

-   (i′) providing a liquid feed stream comprising an alkene, preferably    propene, hydrogen peroxide, a solvent, preferably, acetonitrile,    water, the at least one, dissolved, potassium salt;-   (ii′) passing the liquid feed stream provided in (i′) into an    epoxidation reactor comprising the catalyst comprising a molding    according to the present invention;    wherein in (i′), the molar ratio of potassium relative to hydrogen    peroxide in the liquid feed stream is preferably in the range of    from 5×10⁻⁶:1 to 1000×10⁻⁶:1, preferably from 25×10⁻⁶:1 to    500×10⁻⁶:1, more preferably from 50×10⁻⁶:1 to 250×10⁻⁶:1;    wherein the process preferably comprises-   (iii′) subjecting the liquid feed stream to epoxidation reaction    conditions in the epoxidation reactor, obtaining a reaction mixture    comprising an alkene oxide, preferably propylene oxide, solvent,    preferably acetonitrile, water, the at least one potassium salt, and    optionally non-epoxidized alkene, preferably non-epoxidized propene.

Yet further, the present invention relates to a process for preparing analkene oxide, preferably propylene oxide, said process comprising

-   (i′) providing a liquid feed stream comprising an alkene, preferably    propene, hydrogen peroxide, a solvent, preferably, acetonitrile,    water, the at least one, dissolved, potassium salt;-   (ii′) passing the liquid feed stream provided in (i′) into an    epoxidation reactor comprising the catalyst comprising a molding    according to the present invention;-   (iii′) subjecting the liquid feed stream to epoxidation reaction    conditions in the epoxidation reactor, obtaining a reaction mixture    comprising an alkene oxide, preferably propylene oxide, solvent,    preferably acetonitrile, water, the at least one potassium salt, and    optionally non-epoxidized alkene, preferably non-epoxidized propene;    wherein in (i′), the molar ratio of potassium relative to hydrogen    peroxide in the liquid feed stream is preferably in the range of    from 5×10⁻⁶:1 to 1000×10⁻⁶:1, preferably from 25×10⁻⁶:1 to    500×10⁻⁶:1, more preferably from 50×10⁻⁶:1 to 250×10⁻⁶:1.

The present invention is further illustrated by the following set ofembodiments and combinations of embodiments resulting from thedependencies and back-references as indicated. In particular, it isnoted that in each instance where a range of embodiments is mentioned,for example in the context of a term such as “The process of any one ofembodiments 1 to 4”, every embodiment in this range is meant to beexplicitly disclosed for the skilled person, i.e. the wording of thisterm is to be understood by the skilled person as being synonymous to“The process of any one of embodiments 1, 2, 3, and 4”.

-   1. A process for preparing a molding comprising zinc and a    titanium-containing zeolitic material having framework type MWW,    comprising    -   (i) providing a molding comprising a titanium-containing        zeolitic material having framework type MWW;    -   (ii) preparing an aqueous suspension comprising a zinc source        and the molding comprising a titanium-containing zeolitic        material having framework type MWW prepared in (i);    -   (iii) heating the aqueous suspension prepared in (ii) under        autogenous pressure to a temperature of the liquid phase of the        aqueous suspension in the range of from 100 to 200° C.,        obtaining an aqueous suspension comprising a molding comprising        zinc and a titanium-containing zeolitic material having        framework type MWW;    -   (iv) separating the molding comprising zinc and a        titanium-containing zeolitic material having framework type MWW        from the liquid phase of the suspension obtained in (iii).-   2. The process of embodiment 1, wherein the molding provided in (i)    comprises the titanium-containing zeolitic material having framework    type MWW and a binder.-   3. The process of embodiment 2, wherein at least 90 weight-%,    preferably at least 95 weight-%, more preferably at least 99    weight-%, more preferably at least 99.9 weight-% of the molding    provided in (i) consist of the titanium-containing zeolitic material    having framework type MWW and the binder.-   4. The process of embodiment 2 or 3, wherein in the molding provided    in (i), the weight ratio of the titanium-containing zeolitic    material having framework type MWW relative to the binder is in the    range of from 1:1 to 9:1, preferably in the range of from 2:1 to    7:1, more preferably in the range of from 3:1 to 5:1, wherein the    binder is preferably a silica binder.-   5. The process of any one of embodiments 1 to 4, wherein the molding    provided in (i) is in the form of a tablet, a sphere, a cylinder, a    star, a strand, or a trilob, wherein the molding is preferably a    strand, more preferably an extrudate strand, preferably having    rectangular, triangular hexagonal, quadratic, oval, or circular    cross-section, wherein the diameter of the preferred circular    cross-section is preferably in the range of from 1.0 to 2.0 mm.-   6. The process of any one of embodiments 1 to 5, wherein the molding    provided in (i) exhibits one or more of the following    characteristics (1) to (3), preferably two or more of the following    characteristics (1) to (3), more preferably the following    characteristics (1) to (3):    -   (1) a BET specific surface area of at least 300 m²/g determined        as described in Reference Example 1 herein;    -   (2) a pore volume of at least 0.9 mL/g, determined as described        in Reference Example 2 herein;    -   (3) a mechanical strength in the range of from 5 to 10 N,        preferably in the range of from 6 to 9 N, determined as        described in Reference Example 3 herein.-   7. The process of any one of embodiments 1 to 6, preferably of any    one of embodiments 2 to 6, wherein the molding comprising the    titanium-containing zeolitic material having framework type MWW    provided in (i) is obtainable or obtained by a process comprising    -   (i.1) preparing a mixture comprising the titanium-containing        zeolitic material having framework type MWW, a binder or a        source of a binder, a pasting agent and optionally a        pore-forming agent;    -   (i.2) shaping the mixture prepared in (i.1), obtaining a molding        comprising the titanium-containing zeolitic material having        framework type MWW and a binder or a source of a binder:    -   (i.3) drying the molding obtained in (i.2);    -   (i.4) calcining the dried molding obtained in (i.3), obtaining        the molding comprising the titanium-containing zeolitic material        having framework type MWW and a binder.-   8. The process of any one of embodiments 1 to 6, preferably of any    one of embodiments 2 to 6, wherein providing the molding according    to (i) comprises    -   (i.1) preparing a mixture comprising the titanium-containing        zeolitic material having framework type MWW, a binder or a        source of a binder, and a pasting agent;    -   (i.2) shaping the mixture prepared in (i.1), obtaining a molding        comprising the titanium-containing zeolitic material having        framework type MWW and a binder or a source of a binder:    -   (i.3) drying the molding obtained in (i.2);    -   (i.4) calcining the dried molding obtained in (i.3), obtaining        the molding comprising the titanium-containing zeolitic material        having framework type MWW and a binder.-   9. The process of embodiment 7 or 8, wherein the pasting agent    according to (i.1) comprises one or more of water and a    carbohydrate, preferably water and a carbohydrate.-   10. The process of any one of embodiments 7 to 9, wherein the    mixture prepared in (i.1) comprises a pore-forming agent, preferably    a mesopore-forming agent, which is preferably one or more a    polyalkylene oxide such as polyethylene oxide, a polystyrene, a    polyacrylate, a polymethacrylate, a polyolefin, a polyamide, and a    polyester.-   11. The process of any one of embodiments 7 to 10, wherein the    mixture prepared in (i.1) does not comprise a mesopore-forming    agent, preferably does not comprise a pore-forming agent, which is    preferably one or more of a polyalkylene oxide such as polyethylene    oxide, a polystyrene, a polyacrylate, a polymethacrylate, a    polyolefin, a polyamide, and a polyester.-   12. The process of any one of embodiments 7 to 11, wherein the    binder or precursor of a binder is a silica binder or a precursor of    a silica binder, wherein more preferably, the silica binder or the    precursor comprises, preferably is, colloidal silica.-   13. The process of any one of embodiments 7 to 12, wherein in the    mixture prepared in (i.1), the weight ratio of the    titanium-containing zeolitic material having framework type MWW    relative to the silica comprised in the binder or the precursor of    the binder is in the range of from 1:1 to 9:1, preferably in the    range of from 2:1 to 7:1, more preferably in the range of from 3:1    to 5:1.-   14. The process of any one of embodiments 7 to 13, wherein the    mixture prepared in (i.1) does not comprise zinc.-   15. The process of any one of embodiments 7 to 14, wherein at least    99 weight-%, preferably at least 99.5 weight-%, more preferably at    least 99.9 weight-% of the mixture prepared in (i.1) consist of the    titanium-containing zeolitic material having framework type MWW, the    binder or the precursor of the binder, and the pasting agent.-   16. The process of any one of embodiments 7 to 15, wherein preparing    the mixture according to (i.1) comprises kneading the mixture.-   17. The process of any one of embodiments 7 to 16, wherein shaping    according to (i.2) comprises extruding the mixture prepared in    (i.1).-   18. The process of embodiment 17, wherein from extruding, a molding    is obtained in the form of a strand, preferably having a diameter in    the range of from 1.0 to 2.0 mm.-   19. The process of any one of embodiments 7 to 18, wherein according    to (i.3), the molding is dried at a temperature in the range of from    80 to 200° C., preferably in the range of from 90 to 175° C., more    preferably in the range of from 100 to 150° C.-   20. The process of any one of embodiments 7 to 19, wherein according    to (i.3), the molding is dried in a gas atmosphere comprising    oxygen, preferably in air or lean air, more preferably in air.-   21. The process of any one of embodiments 7 to 20, wherein according    to (i.4), the molding is calcined at a temperature in the range of    from 350 to 650° C., preferably in the range of from 400 to 600° C.,    more preferably in the range of from 450 to 550° C.-   22. The process of any one of embodiments 7 to 21, wherein according    to (i.4), the molding is calcined in a gas atmosphere comprising    oxygen, preferably in air or lean air, more preferably in air.-   23. The process of any one of embodiments 1 to 22, wherein at least    99 weight-% of the titanium-containing zeolitic material having    framework type MWW comprised in the molding provided in (i) consist    of Ti, Si, 0, and H.-   24. The process of any one of embodiments 1 to 23, wherein the    titanium-containing zeolitic material having framework type MWW    comprised in the molding provided in (i) has a titanium content,    calculated as elemental titanium, in the range of from 0.1 to 5    weight-%, preferably in the range of from 0.5 to 3 weight-%, more    preferably in the range of from 1 to 3 weight-%, based on the total    weight of the titanium-containing zeolitic material having framework    type MWW.-   25. The process of any one of embodiments 1 to 24, wherein the    titanium-containing zeolitic material having framework type MWW    comprised in the molding provided in (i) has a silicon content,    calculated as elemental silicon, in the range of from 30 to 60    weight-%, preferably in the range of from 35 to 55 weight-%, more    preferably in the range of from 40 to 50 weight-%, more preferably    in the range of from 1 to 3 weight-%, based on the total weight of    the titanium-containing zeolitic material having framework type MWW.-   26. The process of any one of embodiments 1 to 25, wherein the    titanium-containing zeolitic material having framework type MWW    comprised in the molding provided in (i) has a total organic carbon    content of at most 0.1 weight-%, based on the total weight of the    titanium-containing zeolitic material having framework type MWW.-   27. The process of any one of embodiments 1 to 26, wherein the    titanium-containing zeolitic material having framework type MWW    comprised in the molding provided in (i) has a boron content,    calculate as elemental boron, of at most 0.5 weight-%, based on the    total weight of the titanium-containing zeolitic material having    framework type MWW.-   28. The process of any one of embodiments 1 to 27, wherein the    titanium-containing zeolitic material having framework type MWW    comprised in the molding provided in (i) has a BET specific surface    area of at least 400 m²/g, preferably in the range of from 400 to    600 m²/g, more preferably in the range of from 450 to 550 m²/g,    wherein the BET specific surface area is determined as described in    Reference Example 1 herein.-   29. The process of any one of embodiments 1 to 28, wherein the    titanium-containing zeolitic material having framework type MWW    comprised in the molding provided in (i) has a crystallinity of at    least 70%, preferably in the range of from 70 to 90%, more    preferably in the range of from 70 to 80%, wherein the crystallinity    is determined as described in Reference Example 4 herein.-   31. The process of any one of embodiments 1 to 30, wherein the    titanium-containing zeolitic material having framework type MWW    comprised in the molding provided in (i) is in the form of a powder    having a particle size distribution characterized by a Dv10 value in    the range of from 1 to 10 micrometer, preferably in the range of    from 1.5 to 10 micrometer, more preferably in the range of from 2 to    6 micrometer, a Dv50 value in the range of from 5 to 50 micrometer,    preferably in the range of from 7 to 50 micrometer, more preferably    in the range of from 8 to 30 micrometer, and a Dv90 value in the    range of from 12 to 200 micrometer, preferably in the range of from    12 to 90 micrometer, more preferably in the range of from 13 to 70    micrometer, wherein the particle size distribution is determined as    described in Reference Example 5 herein.-   32. The process of any one of embodiments 1 to 31, wherein the    titanium-containing zeolitic material having framework type MWW    comprised in the molding provided in (i) is a spray powder.-   33. The process of any one of embodiments 1 to 32, wherein in (ii),    the zinc source comprises a zinc compound which is soluble in water    at the temperature and pressure of the liquid aqueous phase    according to (iii).-   34. The process of any one of embodiments 1 to 33, wherein in (ii),    the zinc source comprises one or more of a zinc salt soluble in    water preferably being a zinc salt of an organic or inorganic acid,    preferably comprises one or more of zinc acetate, zinc benzoate,    zinc borate, zinc bromide, zinc chloride, zinc formate, zinc    gluconate, zinc lactate, zinc laurate, zinc malate, zinc nitrate,    zinc perborate, zinc sulfate, zinc sulfamate, zinc tartrate, more    preferably comprises zinc acetate, more preferably comprises zinc    acetate dihydrate.-   35. The process of any one of embodiments 1 to 34, wherein in (ii),    the zinc source comprises zinc acetate, preferably comprises zinc    acetate dihydrate, more preferably is zinc acetate dihydrate.-   36. The process of any one of embodiments 1 to 35, wherein in the    aqueous suspension prepared in (ii), the weight ratio of zinc    comprised in the zinc source relative to the titanium-containing    zeolitic material having framework type MWW comprised in the molding    is in the range of from 0.005:1 to 0.1:1, preferably in the range of    from 0.01:1 to 0.075:1, more preferably in the range of from 0.02:1    to 0.05:1, more preferably in the range of from 0.03:1 to 0.04:1.-   37. The process of any one of embodiments 1 to 36, wherein in the    aqueous suspension prepared in (ii), the weight ratio of the    titanium-containing zeolitic material having framework type MWW    comprised in the molding relative to water is in the range of from    0.01:1 to 0.1:1, preferably in the range of from 0.02:1 to 0.075:1,    more preferably in the range of from 0.03:1 to 0.05:1.-   38. The process of any one of embodiments 1 to 37, wherein at least    99 weight-%, preferably at least 99.5 weight-%, more preferably at    least 99.9 weight-% of the aqueous suspension prepared in (ii)    consist of water, the zinc source and the molding comprising the    titanium-containing zeolitic material having framework type MWW.-   39. The process of any one of embodiments 1 to 38, wherein in (iii),    the suspension prepared in (ii) is heated to and kept at a    temperature of the liquid phase of the aqueous suspension in the    range of from 110 to 175° C., preferably in the range of from 120 to    150° C.-   40. The process of any one of embodiments 1 to 39, wherein in (iii),    the suspension prepared in (ii) is kept at the temperature for a    period of time in the range of from 1 to 24 hours, preferably in the    range of from 2 to 17 hours, more preferably in the range of from 3    to 10 hours.-   41. The process of any one of embodiments 1 to 40, wherein during    heating and keeping in (iii), the suspension prepared in (ii) is not    stirred.-   42. The process of any one of embodiments 1 to 41, wherein in (iv),    the separating comprises subjecting the aqueous suspension obtained    from (iii) to filtration or centrifugation, optionally followed by    washing, obtaining the separated molding comprising zinc and a    titanium-containing zeolitic material having framework type MWW.-   43. The process of any one of embodiments 1 to 42, further    comprising    -   (v) drying the separated molding comprising zinc and a        titanium-containing zeolitic material having framework type MWW        obtained from (iv).-   44. The process of embodiment 43, wherein the separated molding    comprising zinc and a titanium-containing zeolitic material having    framework type MWW is dried at a temperature in the range of from 80    to 200° C., preferably in the range of from 90 to 175° C., more    preferably in the range of from 100 to 150° C.-   45. The process of embodiment 43 or 44, wherein the separated    molding comprising zinc and a titanium-containing zeolitic material    having framework type MWW is dried for a period of time in the range    of from 0.5 to 12 hours, preferably in the range of from 1 to 8    hours, more preferably in the range of from 2 to 6 hours.-   46. The process of any one of embodiments 43 to 45, wherein the    separated molding comprising zinc and a titanium-containing zeolitic    material having framework type MWW is dried in a gas atmosphere    comprising oxygen, preferably air or lean air, more preferably air.-   47. The process of any one of embodiments 43 to 46, further    comprising    -   (vi) calcining the dried molding comprising zinc and a        titanium-containing zeolitic material having framework type MWW        obtained from (v).-   48. The process of embodiment 47, wherein the dried molding    comprising zinc and a titanium-containing zeolitic material having    framework type MWW is calcined at a temperature in the range of from    300 to 600° C., preferably in the range of from 350 to 550° C., more    preferably in the range of from 400 to 500° C.-   49. The process of embodiment 47 or 48, wherein the dried molding    comprising zinc and a titanium-containing zeolitic material having    framework type MWW is calcined for a period of time in the range of    from 0.1 to 6 hours, preferably in the range of from 0.2 to 4 hours,    more preferably in the range of from 0.5 to 3 hours.-   50. The process of any one of embodiments 47 to 49, wherein the    dried molding comprising zinc and a titanium-containing zeolitic    material having framework type MWW is calcined in a gas atmosphere    comprising oxygen, preferably air or lean air, more preferably air.-   51. The process of any one of embodiments 1 to 50, wherein the    molding comprising zinc and a titanium-containing zeolitic material    having framework type MWW is not subjected to water-steaming,    preferably is not subjected to steaming.-   52. A molding comprising zinc and a titanium-containing zeolitic    material having framework type MWW, obtainable or obtained or    preparable or prepared by a process according to any one of    embodiments 1 to 51, preferably according to any one of embodiments    33 to 51, more preferably according to any one of embodiments 43 to    51, more preferably according to any one of embodiments 47 to 51.-   53. A molding comprising zinc and a titanium-containing zeolitic    material having framework type MWW, preferably the molding according    to embodiment 52, wherein in the molding, the weight ratio of zinc    relative to the titanium-containing zeolitic material having    framework type MWW is in the range of from 0.005:1 to 0.1:1,    preferably in the range of from 0.01:1 to 0.075:1, more preferably    in the range of from 0.02:1 to 0.05:1, more preferably in the range    of from 0.03:1 to 0.04:1.-   54. The molding of embodiment 53, wherein at least 99 weight-%,    preferably at least 99.5 weight-% of the molding consist of zinc,    Ti, Si, 0, and H.-   55. The molding of embodiment 53 to 54, having a BET specific    surface are of at least 200 to m²/g, preferably of at least 250    m²/g, wherein the BET specific surface area is determined as    described in Reference Example 1 herein.-   56. The molding of any one of embodiments 53 to 55, having a    crystallinity of at least 50%, preferably in the range of from 50 to    90%, wherein the crystallinity is determined as described in    Reference Example 4 herein.-   57. The molding of any one of embodiments 53 to 56, having a    porosity of at least 0.9 mL/g, determined as described in Reference    Example 2 herein.-   58. The molding of any one of embodiments 53 to 57, having a    mechanical strength in the range of from 9 to 23 N, preferably in    the range of from 11 to 18 N, more preferably in the range of from    15 to 18 N, determined as described in Reference Example 3 herein.-   59. The molding of any one of embodiments 53 to 57, exhibiting a    water adsorption capacity in the range of from 5 to 14 weight-%,    preferably in the range of from 6 to 13 weight-%, more preferably in    the range of from 8 to 12 weight-%, determined as described in    Reference Example 7 herein.-   60. The molding of any one of embodiments 53 to 59, exhibiting a PO    test parameter of at least 8%, preferably of at least 9%, determined    as described in Reference Example 6 herein.-   61. Use of a molding according to any one of embodiments 52 to 60 as    a catalyst for converting a hydrocarbon, preferably as a catalyst    for oxidizing a hydrocarbon, more preferably for epoxidizing a    hydrocarbon having at least one carbon-carbon double bond, more    preferably for epoxidizing an alkene.-   62. The use of embodiment 61 for epoxidizing one or more of propene,    ethene, 1-butene, 2-butene, 1-pentene and 2-pentene, preferably for    epoxidizing propene.-   63. The use of embodiment 61 or 62, wherein the alkene, preferably    propene, is epoxidized in the presence of a solvent preferably    comprising a nitrile, more preferably acetonitrile.-   64. The use of embodiment 62 or 63, wherein the propene is    epoxidized with hydrogen peroxide as epoxidizing agent.-   65. A method for catalytically converting a hydrocarbon, preferably    for catalytically oxidizing a hydrocarbon, more preferably for    catalytically epoxidizing a hydrocarbon having at least one    carbon-carbon double bond, more preferably for catalytically    epoxidizing an alkene, wherein the hydrocarbon, preferably the    hydrocarbon having at least one carbon-carbon double bond, more    preferably the alkene is brought into contact with the molding    according to any one of embodiments 52 to 60 as catalyst.-   66. The method of embodiment 65 for catalytically epoxidizing one or    more of propene, ethene, 1-butene, 2-butene, 1-pentene and    2-pentene, preferably for catalytically epoxidizing propene.-   67. The method of embodiment 66, wherein the alkene, preferably    propene, is epoxidized in the presence of a solvent preferably    comprising a nitrile, more preferably acetonitrile.-   68. The method of embodiment 66 or 67, wherein the propene is    epoxidized with hydrogen peroxide as epoxidizing agent.-   69. A catalytic system comprising a catalyst comprising a molding    according to any one of embodiments 52 to 60, and at least one    potassium salt, wherein the at least one potassium salt is selected    from the group consisting of at least one inorganic potassium salt,    at least one organic potassium salt, and combinations of at least    one inorganic potassium salt and at least one organic potassium    salt.-   70. The catalytic system of embodiment 69, wherein the at least one    potassium salt is selected from the group consisting of at least one    inorganic potassium salt selected from the group consisting of    potassium hydroxide, potassium chloride, potassium nitrate, at least    one organic potassium salt selected from the group consisting of    potassium formate, potassium acetate, potassium carbonate, and    potassium hydrogen carbonate, and a combination of at least one of    the at least one inorganic potassium salts and at least one of the    at least one organic potassium salts.-   71. The catalytic system of embodiment 69 or 70 for the epoxidation    of an alkene, preferably propene.-   72. The catalytic system of any one of embodiments 69 to 71,    obtainable or obtained by a preferably continuous process comprising    -   (i′) providing a liquid feed stream comprising an alkene,        preferably propene, hydrogen peroxide, a solvent, preferably,        acetonitrile, water, the at least one, dissolved, potassium        salt;    -   (ii′) passing the liquid feed stream provided in (i′) into an        epoxidation reactor comprising a catalyst comprising a molding        according to any one of embodiments 52 to 60;    -   wherein in (i′), the molar ratio of potassium relative to        hydrogen peroxide in the liquid feed stream is preferably in the        range of from 5×10⁻⁶:1 to 1000×10⁻⁶:1, preferably from 25×10⁻⁶:1        to 500×10⁻⁶:1, more preferably from 50×10⁻⁶:1 to 250×10⁻⁶:1;    -   wherein the process preferably comprises    -   (iii′) subjecting the liquid feed stream to epoxidation reaction        conditions in the epoxidation reactor, obtaining a reaction        mixture comprising an alkene oxide, preferably propylene oxide,        solvent, preferably acetonitrile, water, at least a portion of        the dissolved potassium salt, and optionally non-epoxidized        alkene, preferably non-epoxidized propene.-   73. A preferably continuous process for preparing an alkene oxide,    preferably propylene oxide, said process comprising    -   (i′) providing a liquid feed stream comprising an alkene,        preferably propene, hydrogen peroxide, a solvent, preferably,        acetonitrile, water, and preferably a dissolved potassium salt;    -   (ii′) passing the liquid feed stream provided in (i′) into an        epoxidation reactor comprising a catalyst comprising a molding        according to any one of embodiments 52 to 60;    -   (iii′) subjecting the liquid feed stream to epoxidation reaction        conditions in the epoxidation reactor, obtaining a reaction        mixture comprising an alkene oxide, preferably propylene oxide,        solvent, preferably acetonitrile, water, at least a portion of        the dissolved potassium salt, and optionally non-epoxidized        alkene, preferably non-epoxidized propene;    -   wherein in (i′), the molar ratio of potassium relative to        hydrogen peroxide in the liquid feed stream is preferably in the        range of from 5×10⁻⁶:1 to 1000×10⁻⁶:1, preferably from 25×10⁻⁶:1        to 500×10⁻⁶:1, more preferably from 50×10⁻⁶:1 to 250×10⁻⁶.

The present invention is further illustrated by the following referenceexamples, examples and comparative examples.

EXAMPLES Reference Example 1: Determination of BET Specific Surface Area

The BET specific surface area (mulitpoint BET specific surface area)referred to in the context of the present application was determined vianitrogen adsorption at 77 K as described in DIN 66131.

Reference Example 2: Determination of Hg Porosimetry Data

The porosimetry data via Hg porosimetry were determined as described inDIN 66133.

Reference Example 3: Determination of Mechanical Strength

The mechanical strength as referred to in the context of the presentinvention is to be understood as determined via a crush strength testmachine Z2.5/TS1S, supplier Zwick GmbH & Co., D-89079 Ulm, Germany. Asto fundamentals of this machine and its operation, reference is made tothe respective instructions handbook “Register 1:Betriebsanleitung/Sicherheitshandbuch für die Material-PrüfmaschineZ2.5/TS15”, version 1.5, December 2001 by Zwick GmbH & Co. TechnischeDokumentation, August-Nagel-Strasse 11, D-89079 Ulm, Germany. With saidmachine, a given strand according to the present invention, described inthe examples herein, is subjected to an increasing force via a plungerhaving a diameter of 3 mm until the strand is crushed. The force atwhich the strand crushes is referred to as the crushing strength of thestrand. The machine is equipped with a fixed horizontal table on whichthe strand is positioned. A plunger which is freely movable in verticaldirection actuates the strand against the fixed table. The apparatus wasoperated with a preliminary force of 0.5 N, a shear rate underpreliminary force of 10 mm/min and a subsequent testing rate of 1.6mm/min. The vertically movable plunger was connected to a load cell forforce pick-up and, during the measurement, moved toward the fixedturntable on which the molding (strand) to be investigated ispositioned, thus actuating the strand against the table. The plunger wasapplied to the stands perpendicularly to their longitudinal axis.Controlling the experiment was carried out by means of a computer whichregistered and evaluated the results of the measurements. The valuesobtained are the mean value of the measurements for 10 strands in eachcase.

Reference Example 4: Determination of the Crystallinity

The crystallinity referred to in the context of the present applicationwas determined according to the method as described in the User ManualDIFFRAC.EVA Version 3, page 105, from Bruker AXS GmbH, Karlsruhe(published February 2003). The respective data were collected on astandard Bruker D8 Advance Diffractometer Series II using a LYNXEYEdetector, from 2° to 50° 2 theta, using fixed slits, a step size of0.02° 2 theta and a scan speed of 2.4 s/step. The parameters used forestimating the background/amorphous content were Curvature=0 andThreshold=0.8.

Reference Example 5: Determination of the Particle Size Distribution

The particle size distribution, referred to in the context of thepresent application on the basis of the respective Dv10, Dv50 and Dv90values, was determined according to the following method: 1.0 g of agiven material was suspended in 100 g deionized water and stirred for 1min. The particle size distribution was then determined using aMastersizer S long bed version 2.15, ser. No. 33544-325; supplier:Malvern Instruments GmbH, Herrenberg, Germany, with the followingparameters:

-   -   focal width: 300RF mm    -   beam length: 10.00 mm    -   module: MS17    -   shadowing: 16.9%    -   dispersion model: 3$$D    -   analysis model: polydisperse    -   correction: none

The term “Dv10 value” as referred to in the context of the presentinvention describes the average particle size where 10 volume-% of theparticles of the micropowder have a smaller size. Similarly, the term“Dv50 value” as referred to in the context of the present inventiondescribes the average particle size where 50 volume-% of the particlesof the micropowder have a smaller size, and the term “Dv90 value” asreferred to in the context of the present invention describes theaverage particle size where 90 volume-% of the particles of themicropowder have a smaller size.

Reference Example 6: PO Test

In the PO test, the moldings of the present invention are tested ascatalysts in a mini autoclave by reaction of propene with an aqueoushydrogen peroxide solution (30 weight-%) to yield propylene oxide. Inparticular, 0.63 g of the moldings of the invention were introducedtogether with 79.2 g of acetonitrile and 12.4 g of propene at roomtemperature, and 22.1 g of hydrogen peroxide (30 weight-% in water) wereintroduced in a steel autoclave. After a reaction time of 4 hours at 40°C., the mixture was cooled and depressurized, and the liquid phase wasanalyzed by gas chromatography with respect to its propylene oxidecontent. The propylene oxide content of the liquid phase (in weight-%)is the result of the PO test.

The PO test rate was determined following the pressure progressionduring the PO test described above. The pressure progression wasrecorded using a S-11 transmitter (from Wika Alexander Wiegand SE & Co.KG), which was positioned in the pressure line of the autoclave, and agraphic plotter Buddeberg 6100A. The respectively obtained data wereread out and depicted in a pressure progression curve. The pressure droprate, i.e. the PO test rate, was determined according to the followingequation:

PDR=[p(max)−p(min)]/delta t

wherein

-   PDR/(bar/min)=pressure drop rate-   p(max)/bar=maximum pressure at the start of the reaction-   p(min)/bar=minimum pressure observed during the reaction-   delta t/min=time difference from the start of the reaction to the    point in time where p(min) was observed

Reference Example 7: Determination of Water Adsorption

The water adsorption/desorption isotherms measurements were performed ona VTI SA instrument from TA Instruments following a step-isothermprogram. The experiment consisted of a run or a series of runs performedon a sample material that has been placed on the microbalance pan insideof the instrument. Before the measurement were started, the residualmoisture of the sample was removed by heating the sample to 100° C.(heating ramp of 5° C./min) and holding it for 6 h under a N₂ flow.After the drying program, the temperature in the cell was decreased to25° C. and kept isothermal during the measurements. The microbalance wascalibrated, and the weight of the dried sample was balanced (maximummass deviation 0.01 wt. %). Water uptake by the sample was measured asthe increase in weight over that of the dry sample. First, an adsorptioncurve was measured by increasing the relative humidity (RH) (expressedas weight-% water in the atmosphere inside of the cell) to which thesamples was exposed and measuring the water uptake by the sample atequilibrium. The RH was increased with a step of 10 wt. % from 5 to 85%and at each step the system controlled the RH and monitored the sampleweight until reaching the equilibrium conditions and recording theweight uptake. The total adsorbed water amount by the sample was takenafter the sample was exposed to the 85 weight-% RH. During thedesorption measurement the RH was decreased from 85 wt. % to 5 wt. %with a step of 10% and the change in the weight of the sample (wateruptake) was monitored and recorded.

Reference Example 8: Preparation of a Titanium-Containing ZeoliticMaterial Having Framework Type MWW

A titanium-containing zeolite (spray powder) was prepared as describedin Example 5, 5.1 to 5.3, of WO 2013/117536 A, page 83, line 26 to page92, line 7.

Reference Example 9: Continuous Epoxidation Reaction

Continuous epoxidation reaction was carried out as described in WO2015/010990 A, in Reference Example 1, page 55, line 14 to page 57, line10. The reaction temperature was set to a value of 45° C. (see WO2015/010990 A, page 56, lines 16 to 18). The temperature was adjusted toachieve an essentially constant hydrogen peroxide conversion of 90% (seeWO 2015/010990 A, page 56, lines 21 to 23). KH₂PO₄ was employed asadditive (see WO 2015/010990 A, page 56, lines 7 to 10), theconcentration of the additive was 130 micromol per mol hydrogenperoxide. As catalysts, the catalysts according to Comparative Example 1and Example 1 hereinbelow were employed (see WO 2015/010990 A, page 55,lines 16 to 18).

Reference examples 10 to 12 which follow herewith are examples of how toprovide a titanium-containing zeolitic material having framework typeMWW, having a water absorption capacity of at least 11 weight-%.

Reference Example 10: Providing a Titanium-Containing Zeolitic MaterialHaving Framework Type MWW, Having a Water Absorption Capacity of atLeast 11 Weight-% (i) B—Ti-MWW Synthesis

The synthesis mixture had the following composition: 1.0 (SiO₂): 0.04(TiO₂): 0.67 (B₂O₃): 1.4 piperidine: 19 H₂O.

Batch 0: 1,026 g of deionized water were initially introduced into abeaker, 365 g of piperidine were then added with stirring at 200 rpm,and the mixture was stirred for 10 min at pH 13.2 at about 23° C.Thereafter, the batch was divided into two equal parts.

Batch 1: 695.5 g of the deionized water-piperidine solution were placedin a beaker and, with stirring at 200 rpm, 248.4 g of boric acid wereadded and stirring was continued for 30 min, then 90 g of fumed silica(Cab-O-SIL® 5M) was added at about 23° C. The mixture was then stirredfor 1 h at pH 11.4 at about 23° C.

Batch 2: 695.5 g of the deionized water-piperidine solution wereinitially introduced into a beaker, with stirring at 200 rpm at about23° C., 43.2 g of tetrabutyl orthotitanate were added and stirring wascontinued for a further 30 minutes and then 90 g of fumed silica(Cab-O-SIL® 5M) were added. The mixture was then stirred for 1 h at pH12.2 at about 23° C.

Batch 3: The two suspensions from batch 1 and 2 were mixed together for1.5 h at pH 11.8 at about 23° C. to obtain the synthesis mixture andthen crystallization was carried out in an autoclave under the followingconditions:

Heating in 1 h to 130° C./keeping for 24 h at 100 rpm at a pressure offrom 0-2.7 bar, then,

heating in 1 h to 150° C./keeping for 24 h at 100 rpm at a pressure offrom 2.7-4.9 bar, then,

heating in 1 h to 170° C./keeping for 120 h at 100 rpm at a pressure offrom 4.9-9.4 bar.

After the above crystallization conditions, the thus obtained suspensionhaving a pH of 11.3 was drained and filtered through a suction filter(giving a clear filtrate) and washed with 10 liters of deionized water(giving a turbid filtrate). The turbid filtrate was then acidified to pH7 with 10% aqueous HNO₃. Subsequently, the moist product (filter cake)was filled into a porcelain dish, dried overnight, then ground. Theyield was 192.8 g. According to the elemental analysis the resultingproduct had the following contents determined per 100 g substance of 9.6g carbon, 0.85 g B, 21.8 g Si and 17.8 g Ti.

(ii) B—Ti-MWW HNO₃ Treatment

The dried and ground material obtained according to item (i) above waswashed with HNO₃ solution (ratio of solid to liquid 1 g:20 ml) for 20 hat 100° C.: In a 10 liter glass flask 3600 g HNO₃ solution and 180 gB—Ti-MWW according to item (i) were added at 100° C., followed byboiling for 20 hours at reflux with stirring at 250 rpm. The thusobtained white suspension was filtered off and washed with 2×5 liters ofdeionized water. Drying: 10 h/120° C. Calcination: heating at 2 K/min to530° C./keeping for 5 h. The yield was 143 g. According to the elementalanalysis the resulting product had the following contents determined per100 g substance: <0.1 g carbon (TOC), 0.27 g B, 42 g Si, and 2 g Ti. TheBET surface area was determined to be 532 m²/g. The crystallinity of theproduct was measured (Reference Example 8) to be 80% and the averagecrystal size as calculated from the XRD diffraction data was determinedto be 22 nm.

(iii) B—Ti-MWW HNO₃ Treatment

The material obtained according to item (ii) above was washed with HNO₃solution (ratio of solid to liquid 1 g:20 ml) for 20 h at 100° C. In a10 liter glass flask, 2,400 g of HNO₃ solution and 120 g of B—Ti-MWWaccording to item (ii) were added at 100° C., followed by boiling for 20hours at reflux with stirring at 250 rpm. The white suspension wasfiltered off and washed with 7×1 liter of deionized water. Drying: 10h/120° C. Calcination: heating at 2 K/min to 530° C./keeping for 5 h.The yield was 117 g. According to the elemental analysis the resultingproduct had the following contents determined per 100 g substance: <0.03g B, 44 g Si, and 1.8 g Ti. The BET specific surface area was determinedto be 501 m²/g. The crystallinity of the product was measured to be 94%and the average crystal size as calculated from the XRD diffraction datawas determined to be 22 nm. The XRD of the resulting product confirmedthat the zeolitic material obtained had an MWW framework structure. Thewater adsorption capacity as determined by Reference Example 1 hereinwas 13.2 weight-%.

Reference Example 11: Providing a Titanium-Containing Zeolitic MaterialHaving Framework Type MWW, Having a Water Absorption Capacity of atLeast 11 Weight-% (i) B—Ti-MWW Synthesis

The synthesis mixture had the following composition: 1.0 (SiO₂): 0.04(TiO₂): 0.67 (B₂O₃): 1.4 piperidine: 19 H₂O.

Batch 0: 1,026 g of deionized water were initially introduced into abeaker, 365 g of piperidine were added with stirring at 200 rpm, and themixture was stirred for 10 min at pH 13.2 at about 23° C. Thereafter,the batch was divided into two equal parts.

Batch 1: 695.5 g of deionized water-piperidine solution were placed in abeaker and, with stirring at 200 rpm, 248.4 g of boric acid were addedand stirring was continued for 30 minutes, then 90 g of fumed silica(Cab-O-SIL® 5M) were added at about 23° C. The mixture was then furtherstirred for 1 h at pH 11.4 at about 23° C.

Batch 2: 695.5 g of deionized water-piperidine solution were initiallyintroduced into a beaker, with stirring at 200 rpm at about 23° C., 43.2g of tetrabutyl orthotitanate were added and stirring was continued fora further 30 min and then 90 g of fumed silica (Cab-O-SIL® 5M) wereadded. The mixture was then further stirred for 1 h at pH 12.2 at about23° C.

Batch 3: The two suspensions from batch 1 and 2 were mixed together for1.5 h at a pH of 11.8 at about 23° C. to obtain the synthesis mixtureand then crystallization was carried out in an autoclave under thefollowing conditions: heating in 1 h to 170° C./keeping for 120 h at 120rpm at a pressure of from 0-9.4 bar. After the above crystallizationconditions, the thus obtained suspension having a pH of 11.3 was drainedand filtered through a suction filter and washed with 10 L of deionizedwater. Subsequently, the moist product (filter cake) was filled into aporcelain dish, dried overnight, then ground. The yield was 194 g.

(ii) B—Ti-MWW HNO₃ Treatment

The dried and ground material according to item (i) was then washed withHNO₃ solution (ratio of solid to liquid 1 g:20 ml) for 20 h at 100° C.:In a 10 liter glass flask 3,600 g aqueous HNO₃ solution and 180 gB—Ti-MWW according to item (i) were added at 100° C., followed byboiling for 20 h at reflux with stirring at 250 rpm. The thus obtainedwhite suspension was filtered off and washed with 2×5 L of deionizedwater. Drying: 10 h/120° C. Calcination: heating at 2 K/min to 530°C./keeping for 5 h. The yield was 146 g. According to the elementalanalysis the resulting product had the following contents determined per100 g substance: <0.1 g carbon (TOC), 0.25 g B, 43 g Si and 2.6 g Ti.The BET specific surface area was determined to be 514 m²/g. Thecrystallinity of the product was measured to be 79% and the averagecrystal size as calculated from the XRD diffraction data was determinedto be 22.5 nm. The XRD of the resulting product confirmed that thezeolitic material obtained had an MWW framework structure. The wateradsorption capacity as determined by Reference Example 1 herein was 17.3weight-%.

Reference Example 12: Providing a Titanium-Containing Zeolitic MaterialHaving Framework Type MWW, Having a Water Absorption Capacity of atLeast 11 Weight-% (i) B—Ti-MWW Synthesis

In order to prepare a synthesis mixture having the followingcomposition: 1.0 B₂O₃/2.0 SiO₂/32.8 H₂O/2.43 piperidine, deionized waterand boric acid were mixed together in a beaker at about 23° C., to whichammonium stabilized silica sol was added with further mixing at about23° C. The thus obtained mixture was then transferred to an autoclaveand piperidine was then added with further mixing. Crystallization wasthen carried out in the autoclave over 48 hours at 175° C. at autogenouspressure. Any excess piperidine was then flashed off. The resultingproduct was then filtered off as a solid, washed with deionized waterand dried. Rotary calcination was then carried out at 650° C. for 2hours.

(ii) Deboronation

A slurry of the thus obtained calcined product was then prepared withdeionised water, such that the slurry had a solids content of 6.25weight-%. The slurry was heated to 90.5° C. and then held at saidtemperature for 10 hours. The resulting (deboronated) product was thenfiltered off as a solid, washed with deionized water and dried.

(iii) Ti Insertion

A slurry was prepared with the deionized water and the deboronatedproduct of item (ii) above, which was mixed at 23° C. Said slurry wasthen transferred to an autoclave, to which a tetra-n-butyltitanate/piperidine mixture was then added. The thus obtained mixturehad the following composition: 0.035 TiO₂/1.0 SiO₂/17.0 H₂O/1.0Piperidine. Crystallization was then carried out in the autoclave over48 hours at 170° C. under autogenous pressure. Any excesspiperidine/ethanol was then flashed off. The resulting product was thenfiltered off as a solid, washed with deionized water and dried.

(iv) Acid Treatment

A slurry was prepared from the product according to item (iii) in 10%HNO₃ (aqueous) solution (907.2 g HNO₃/453.6 g product of item (iii),thus a 5 weight-% solids slurry was produced. The slurry was heated to93.3° C. and then held at said temperature for 1 hour. The resultingproduct was then filtered off as a solid, washed with deionized waterand dried. Rotary calcination was then carried out at 650° C. for 2hours. According to the elemental analysis the resulting calcinatedproduct had the following contents determined per 100 g substance of 2 gcarbon (TOC), 42 g Si and 1.6 g Ti. The BET specific surface area wasdetermined to be 420 m²/g. The crystallinity of the product was measuredto be 82%. The XRD of the resulting product confirmed that the zeoliticmaterial obtained had an MWW framework structure. The water adsorptioncapacity as determined by Reference Example 1 herein was 14.1 weight-%.

Comparative Example 1: Preparation of a Molding a Zinc- andTitanium-Containing Zeolitic Material Having Framework Type MWW

Using the titanium-containing zeolite prepared according to ReferenceExample 8 above, a molding was prepared. In a first step CE1.1, thetitanium-containing zeolite was impregnated with zinc so as to obtain azinc- and titanium-containing zeolitic material having framework typeMWW. In a second step CE1.2, the zinc- and titanium-containing zeoliticmaterial having framework type MWW was subjected to shaping. Therespectively obtained moldings were subjected to a water treatment in athird step CE1.3.

-   CE1.1: The titanium-containing zeolite prepared according to    Reference Example 8 was subjected to zinc impregnation. The    impregnation was carried out as described in WO 2013/117536 A,    example 5.4, page 92, line 9 to page 94, line 8.-   CE1.2: The shaping of the zinc- and titanium-containing zeolitic    material having framework type MWW was carried out as described in    WO 2013/117536 A, example 5.5, page 95, lines 10 to 36.-   CE1.3: The water treatment of the moldings obtained from the second    step was carried out as described in WO 2013/117536 A, example 5.6,    page 97, lines 1 to 17.

Example 1: Preparation of a Molding Comprising Zinc and aTitanium-Containing Zeolitic Material Having Framework Type MWW

Using the titanium-containing zeolite prepared according to ReferenceExample 8 above, a molding was prepared. In a first step E1.1, thetitanium-containing zeolite was subjected to shaping. In a second stepE1.2, the respectively obtained moldings were subjected to a watertreatment wherein during said water treatment, zinc was incorporatedinto the moldings.

-   E1.1: 60 g of the titanium-containing zeolite prepared according to    Reference Example 8 were admixed with 3 g of Walocel™ (5%; Wolf    Walsrode AG) and 37.5 g Ludox® AS-40 (20 weight-% SiO₂ relative to    zeolitic material) and kneaded for 10 min. Them 160 mL deionized    water were added, and the resulting mixture was kneaded further. The    total kneading time was 40 min. In a Loomis extruder, strands were    prepared at a machine pressure of 54 bar from the kneaded mass,    wherein said strands had a circular cross section with a diameter of    1.5 mm. In an oven, the strands were heated to a temperature of    120° C. at a heating rate of 3 K/min and dried at 120° C. for 4 h    under air atmosphere. Then, the dried strands were heated to a    temperature of 500° C. at a heating rate of 2 K/min and dried at    500° C. for 5 h under air atmosphere.-   E1.2: 50 g of strands of the calcined strands obtained from E1.1    were added to 1,000 g of deionized water and 4.6 g zinc acetate    dihydrate (Merck) in an autoclave without stirring. The mixture was    heated to a temperature of 145° C. and kept at that temperature for    8 h under the autogenous pressure of 2.8 bar. The resulting strands    were filtered off using a nutsch-type filter and washed five times    with 200 mL of deionized water until the conductivity of the water    obtained from the washing was below 30 microSiemens. In an oven, the    respectively obtained strands were heated to a temperature of    120° C. within 60 min and dried at that temperature for 240 min    under air atmosphere. Then, the dried strands were heated to a    temperature of 450° C. within 165 min and calcined at that    temperature for 120 min under air atmosphere.

Comparative Example 2: Preparation of a Molding a Zinc- andTitanium-Containing Zeolitic Material Having Framework Type MWW

Example 1 was repeated, with the difference that in step E1.2 ratherthan autogeneous pressure, reflux conditions were employed.

More specifically, 50 g of strands of the calcined strands obtained fromE1.1 were added to 1,000 g of deionized water and 4.6 g zinc acetatedihydrate (Merck), which was then heated to 100° C. and stirred atreflux for 8 hours. The resulting strands were filtered off using anutsch-type filter and washed five times with 200 mL of deionized wateruntil the conductivity of the water obtained from the washing was below30 microSiemens. In an oven, the respectively obtained strands wereheated to a temperature of 120° C. within 60 min and dried at thattemperature for 240 min under air atmosphere. Then, the dried strandswere heated to a temperature of 450° C. within 165 min and calcined atthat temperature for 120 min under air atmosphere.

In the following table 1, the results of Comparative Example 1 (CE1),Comparative Example 2 (CE2) and Example 1 (E1) are shown.

TABLE 1 Characteristics of the moldings Strands CE1 CE2 E1 Zncontent/weight-% 1.1 1.2 1.6 Ti content/weight-% 1.4 1.2 1.4 PO test/%^(a)) 8.4 8.3 9.4 PO test rate/bar/min ^(b)) 0.03 0.02 0.05 Selectivityrelative to propene ^(g))/% 99.5 n.d. ^(h)) 99.5 Mechanical strength/N^(c)) 14 5.3 15 Water adsorption capacity/weight-% ^(d)) 7 12.2 11.6Pore volume/mL/g ^(e)) 1.3 1.4 1.5 BET specific surface area/m²/g ^(f))303 347 257 ^(a)) determined as described in Reference Example 6 herein^(b)) determined as described in Reference Example 6 herein ^(c))determined as described in Reference Example 3 herein ^(d)) determinedas described in Reference Example 7 herein ^(e)) determined as describedin Reference Example 2 herein ^(f)) determined as described in ReferenceExample 1 herein ^(g)) the selectivity, after a time on stream of 500 h,was calculated as 100 times the ratio of moles of propylene oxide in theeffluent stream divided by the moles of hydrogen peroxide (consumed) inthe feed stream. The continuous reactions were carried out as describedin Reference Example 9 herein ^(h)) not determined

As shown in Table 1, the zinc content of the molding of the presentinvention was significantly higher (1.6 weight-%) than the zinc contentof the prior art moldings (1.1 weight-%), although for preparing thestrands of the invention, significantly less zinc acetate dihydrate perzeolitic material were employed (11.5%) compared with the prior artaccording to the comparative example 1 (18.4%). Further, with regard tothe PO test as well as with regard to the PO test rate, the use of thestrands according to the invention (E1) lead to significantly improvedvalues compared to the Comparative Examples CE1 and CE2, i.e. theyexhibit improved characteristics for the preferred use of the inventivestrands since the higher the rate, the higher the catalyst activitysince the propene starting material is consumed faster.

Furthermore, as shown in Table 1, E1 (autogenous conditions) showssignificantly improved physical properties over CE2 (reflux conditions).In particular, the mechanical strength of CE2 is much lower (5.3 N forCE2 compared to 15 N for E1), highlighting that if reflux conditions areemployed instead of the autogenous conditions of E1.2, then a product isobtained with inferior physical properties.

CITED LITERATURE

-   WO 2013/117536 A-   WO 2015/010990 A

1. A molding comprising zinc and a titanium-containing zeolitic materialhaving framework type MWW, obtained by a process comprising: (i)providing a molding comprising a titanium-containing zeolitic materialhaving framework type MWW; (ii) preparing an aqueous suspensioncomprising a zinc source and the molding comprising atitanium-containing zeolitic material having framework type MWW preparedin (i); (iii) heating the aqueous suspension prepared in (ii) underautogenous pressure to a temperature of the liquid phase of the aqueoussuspension of from 100 to 200° C., thereby obtaining an aqueoussuspension comprising a molding comprising zinc and atitanium-containing zeolitic material having framework type MWW; and(iv) separating the molding comprising zinc and a titanium-containingzeolitic material having framework type MWW from the liquid phase of thesuspension obtained in (iii).
 2. The molding of claim 1, wherein themolding provided in (i) comprises the titanium-containing zeoliticmaterial having framework type MWW and a binder, wherein in the moldingprovided in (i), the weight ratio of the titanium-containing zeoliticmaterial having framework type MWW relative to the binder is from 1:1 to9:1.
 3. The moldings of claim 1, wherein the molding provided in (i) hasat least one of the following characteristics (1) to (3): (1) a BETspecific surface area of at least 300 m²/g; (2) a pore volume of atleast 0.9 mL/g; (3) a mechanical strength in the range of from 5 to 10N.
 4. The molding of claim 1, wherein at least 99 wt. % of thetitanium-containing zeolitic material having framework type MWWcomprised in the molding provided in (i) consists of Ti, Si, O, and H,wherein the titanium-containing zeolitic material having framework typeMWW comprised in the molding provided in (i) has a titanium content,calculated as elemental titanium, of from 0.1 to 5 wt. %, based on atotal weight of the titanium-containing zeolitic material havingframework type MWW.
 5. The molding of claim 1, wherein thetitanium-containing zeolitic material having framework type MWWcomprised in the molding provided in (i) is in the form of a powderhaving a particle size distribution having a Dv10 value of from 1 to 10micrometer, and a Dv90 value of from 12 to 200 micrometer.
 6. Themolding of claim 1, wherein in (ii), the zinc source comprises a zinccompound which is soluble in water at a temperature and pressure of theliquid aqueous phase according to (iii).
 7. The molding of claim 1,wherein in the aqueous suspension prepared in (ii), a weight ratio ofzinc comprised in the zinc source relative to the titanium-containingzeolitic material having framework type MWW comprised in the molding isfrom 0.005:1 to 0.1:1.
 8. The molding of claim 1, wherein in the aqueoussuspension prepared in (ii), a weight ratio of the titanium-containingzeolitic material having framework type MWW comprised in the moldingrelative to water is from 0.01:1 to 0.1:1.
 9. The molding of claim 1,wherein in (iii), the suspension prepared in (ii) is heated to and keptat a temperature of the liquid phase of the aqueous suspension in therange of from 110 to 175° C.
 10. The molding of claim 1, wherein theprocess further comprises: (v) drying the separated molding comprisingzinc and a titanium-containing zeolitic material having framework typeMWW obtained from (iv); and (vi) calcining the dried molding comprisingzinc and a titanium-containing zeolitic material having framework typeMWW obtained from (v).
 11. A molding comprising zinc and atitanium-containing zeolitic material having framework type MWW, whereinin the molding, a weight ratio of zinc relative to thetitanium-containing zeolitic material having framework type MWW is from0.005:1 to 0.1:1.
 12. The molding of claim 11, having at least one ofthe following characteristics: a BET specific surface are of at least200 to m²/g; a crystallinity of at least 50%; a porosity of at least 0.9mL/g; a mechanical strength of from 9 to 23 N; a water adsorptioncapacity of from 5 to 14 wt. %; and a PO test parameter of at least 8%.13. A process for converting a hydrocarbon, comprising contacting thehydrocarbon with a catalyst comprising the molding of claim
 11. 14. Theprocess of claim 13, wherein the hydrocarbon comprises an alkene, andthe alkene is epoxidized in the presence of a solvent.
 15. The moldingof claim 2, wherein at least 99 wt. % of the molding provided in (i)consist of the titanium-containing zeolitic material having frameworktype MWW and the binder.
 16. The molding of claim 6, wherein the zincsource comprises at least one zinc salt soluble in water.